Philip h



(No Model.)

P. H. MANDEL. Pantograph Plate.

772M0 6- as.

N.PETERS. PNOTO-LITHQGRAPNIERG WASHINGTON, D. C

UNITED. STATES PATENT OFFICE,

PHILIP H, MANDEL, OF BOSTON, MASSACHUSETTS, ASSIGNOR, BY MESNE ASSIGNMENT, TO THE MECHANICAL COMPANY, OF NEW YORK, N. Y.

PANTOGRAPH-PLATE.

SPECIFICATION forming part of Letters Patent No; 240,525, dated April 26, 1881.

Application filed January 12, 1881. (No model.)

To all whom it may concern Be it known that I, PHILIP H. MANDEL,

of Boston, county of Suffolk, and State of Massachusetts, have invented a new and useful Improvement in Pantograph Plates, of which the following description, in connection with the accompanying drawing, is a specification.

, This invention has for its object the production of a novel pantograph-p late, it being produced by a new process, as will be hereinafter described.

Pantograph-plates as now commonly in use are produced bytracing on paper an outline r of the design to be ultimately produced on the printing-roll, the said design being commonly enlarged from five to nine times by means of a camera. The outline of this shadow on this paper is traced by a pencil, and whentraced,

to avoid the reversal of the design on the pantograph-plate as compared with the figure first traced, the paper is turned over and the design already traced on one side of it is portrayed on the opposite side of the said paper, directly opposite the lines already traced, by means of transferring-ink, and this tracing in transferrin g-ink is transferred upon the usual zinc plate, when it is engraved by hand, and is ready for use with the pantograph-machine.

In this my invention I take the usual zinc plate, and having coated it on one side with a sensitized etchin g-ground, such as will be here inafter described, I expose the said plate to rays of light from the usual camera, having in it the design,'which, enlarged, is to be etched on the plate until the said design, more or less enlarged, becomes outlined on the sensitized etching-ground, or I may use any suitable negative by which to produce the design on this sensitized portion of the plate.

The design having been so outlined or portrayed by the effect of light,which, in practice, may he sun-light, or any light commonly employed in photographic processes, the plate is removed and placed in the hands of a suitable person, who, by means of an etching-tool or other proper sharp-pointed instrument, cuts the sensitized etching-ground through to the zinc, following the design thereon developed 50 or portrayed, as before stated, after whichthe plate is subjected to the action of any suitable or usual etching-acid, which, acting only on the parts of the plate exposed by the sharppointed instrument, eats into or etches the plate leaving etched lines corresponding in width with the lines cut through the ground, such lines being more or less Wide, according to the fineness of the tool employed, and consequently I am enabled to etch very fine, sharp lines, lines which may be finer than ordinary 6o engraved lines used in pantograph-Work.

The drawing represents one of my sensitized etched plates, one portion thereof being shown as merely having the design outlined or portrayed on it, while other portions represent -6 5 the same cut through to the plate, and other parts show it etched ready for use in the pantograph-m'achine.

The plate 1), preferably of zinc, after being thoroughly cleaned and dried, is coated on one side with the sensitized etching-ground, composed primarily of asphaltum, having its sensitiveness to light increased by an acid.

After many experiments I have found the following as thematerial for the ground, viz., seven ty-five grams of dry benzine, seven grams of lemon-peel essence, two grams asphaltum, preferably Assyrian, two grams chloroform, and three grams of lavender-oil.

The lemon-peel essence enhances the sensi- 8o tiveness of the asphaltum, the dry benzine and chloroform form a solvent for the asphaltum, While the lavender-oil acts to prevent too rapid drying of the dissolved asphaltum, and secures for the ground proper flexibility to permit the plate to be bent without cracking the ground, and yet leave the ground hard enough to be out by a sharp instrument without ragged lines.

I have above stated the exact proportion of 0 the ingredients I prefer to use, but I wish to state that I do not desire to confine myself to exact proportions; and I also desire to say that instead of the ingredients mentioned as incorporated with the asphaltum I may em- 5 ploy any well known chemical substitute which will serve the purpose herein described-as, for instance, I might employ acetic acid instead of the lemon-peel essence, or turpentine instead of henzine, incorporated in part with it. I00

This mixture is poured on one side of the cleaned plate in a dark room, and is dried artificially, or otherwise, producing a thin smooth ground. The plate so prepared is placed in connection with a camera or negative, and the design in the camera or on the negative is, by the action of sun-light or other suitable or usual light, portrayed, outlined, or shadowed upon this sensitized ground, and after this the plate is taken and the ground is cut through by a sharp-pointed instrument, the lines out through the ground being made along these, portrayed or shadowed thereon from the design in the camera, or from the negative. The ground havingbeen cut through to the plate, the latter, its back having been protected as usual, is then placed in an etching-bath, where it is etched in the usual manner and for any desired depth.

The process herein described is much cheaper than that now commonly in use, and the etched plate has all the merits of the engraved plate,

and the etched plate may be produced in very much less time and by less skilled labor. 7

Referring to the drawing, the unbroken lines a represent the figure as it will be outlined, shadowed, or portrayed upon the sensitized metal plate I). The fine dotted lines 0 are intended to represent the sensitized ground of the plate merely cut through by means of a sharp-pointed tool. The lines d, composed of dashes and dots, are supposed to represent etched lines, they showing the third step of the process herein described, the said etched lines being produced by means of suitable etching-acid acting upon the plate at the parts of it uncovered by cutting through the sensitized ground.

When the plate has been properly etched to present the proper figure, etched into the plate to the proper depth, the sensitized ground will be entirely cleaned off from the surface of the plate b.

I am aware that itis not new to photograph the design to be produced upon glass, paper, or other suitable material, thus making a negative, and then transferring the film to a plate coated with a varnish to resist acid, the varnish and transferred film being subsequently cut through by the etcher, in accordance with the design. on the said film, the plate being afterward etched in the usual manner to form a printing-surface, and such I do not claim, broadly.

I claim- The process of producing pantographic pattern-plates, which consists in coating a metal plate with a sensitized etching-ground, substantially as described, then portraying, outlining, or shadowing on the said ground by or through the effect of light the design to be produced, then cutting through the said ground to the plate with a suitable instrument, and etching the said plate with acid, as set forth.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

PHILIP H ANY MANDEL.

Witnesses FREDERICK P. FISH, J 0s. P. LIVERMORE. 

